Finding the Fourth Proportional to 2,089.72, 3,134.03 and 991.90

Step by Step Solution

1. Step 1: Write the proportion equation
   2,089.72 : 3,134.03 = 991.90 : x
2. Step 2: Convert to fraction form
   2,089.72/3,134.03 = 991.90/x
3. Step 3: Cross multiply
   2,089.72x = 3,134.03 × 991.90
4. Step 4: Simplify right side
   2,089.72x = 3,108,628.69
5. Step 5: Solve for x
   x = 3,108,628.69/2,089.72
6. Step 6: Final answer
   x = 1,487.58